Form 637 Application for Registration (For Certain Excise Tax Act

Form

637

(Rev. December 2022)
Department of the Treasury
Internal Revenue Service

Type or print

Part I

Application for Registration
(For Certain Excise Tax Activities)

OMB No. 1545-1835

Go to www.irs.gov/Form637 for the latest information.

Identification of Applicant

Legal name of entity (or individual) for which the employer identification number (EIN) was secured

Employer identification number (EIN)

Trade name of business if different from above

Telephone number

Mailing address (number, street, and room or suite no.; if P.O. box, see instructions)

Fax number

City or town, state or province, country, and ZIP or foreign postal code
If you listed a P.O. box above, or if your street address is different from your mailing address, list your street address (including city or town, state or province, country,
and ZIP or foreign postal code)

Part II

Activities. Enter the activity letter from the chart on pages 2–5 and a brief description of each activity for which you’re

applying for registration. Also, attach the Additional Information Required for each activity to which this application applies.

Activity Letter

Part III

Activity Description

General Information

Section A—For All Applicants
Answer all the questions below. Attach a separate sheet(s), as needed, to answer lines 2b through 7. Identify each sheet with your
name and employer identification number at the top, and write the number of the line to which each answer applies. If any questions
don’t apply to you, explain why.
1a Are you filing, or will you be required to file, Form 720, Quarterly Federal Excise Tax Return? . . . . .
b Have you previously applied to be registered by any IRS office? . . . . . . . . . . . . . . .
c Have you, or any related entity, had a Certificate of Registry or Letter of Registration revoked or suspended
by any IRS office? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
d If you answered “Yes” to (b) or (c), enter the name of the IRS office
2a List the date your business started: Month
Year
b Explain in detail your business activity.

Yes
Yes

No
No

Yes

No

3

For all other business entities to which you’re related, list:
a The name and EIN of the related entity,
b The percentage of ownership, and
c How you are related (for example, stock, partnership, etc.).

4

List all addresses of current business operations (include out-of-state or foreign operations, if applicable).

5

List the address where your books and records are kept (if different from the address in Part I).

6

List the names and taxpayer identification numbers (TINs) of all business owners, corporate officers, members, or partners.

7

List the name and phone number of a person whom we can contact about this application.

Section B—For All Fuel Applicants
If you’re applying for fuel activities K, M, S, X, Y, AB, AF, AL, AM, CC, NB, QR, SA, SB, UA, UB, UP, or UV, you must complete line 8.
8

Describe any changes in your ownership or changes of controlling stock ownership in the past 2 years. If none, enter “None.”
Also see Changes in Registration in the instructions.

Go to Section C on Page 2
For Privacy Act and Paperwork Reduction Act Notice, see instructions.

Cat. No. 49952H

Form 637 (Rev. 12-2022)

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Form 637 (Rev. 12-2022)

Section C—For Certain Fuel Applicants
If you’re applying for fuel activities K, M, S, or Y, answer each question below by checking the “Yes” or “No” box. If you answer “Yes”
to any of these questions, provide a full explanation. Attach additional sheets if needed.
Have you or any related person (see Regulations section 48.4101-1(b)(5)) been:
9

10
11

12

13
14

Assessed any penalty under chapter 68 of the Internal Revenue Code (or similar provision of the law of any
state) for fraudulently failing to file any return or pay any tax, and the penalty hasn’t been wholly abated,
refunded, or credited?
. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Yes

No

Assessed any penalty under chapter 68 of the Internal Revenue Code, and the penalty hasn’t been wholly
abated, refunded, or credited? . . . . . . . . . . . . . . . . . . . . . . . . . .

Yes

No

Convicted of a crime under chapter 75 of the Internal Revenue Code (or similar provision of the law of any
state), or of conspiracy to commit such a crime, and the conviction hasn’t been wholly reversed by a court of
competent jurisdiction? . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Yes

No

Convicted, under the laws of the United States or any state, of a felony for which an element of the offense is
theft, fraud, or the making of false statements, and the conviction hasn’t been wholly reversed by a court of
competent jurisdiction? . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Yes

No

Assessed any tax under section 4103 (willful failure to pay the tax imposed by section 4041(a)(1) or 4081)
and the tax hasn’t been wholly abated, refunded, or credited? . . . . . . . . . . . . . . .

Yes

No

Advised that your registration has been revoked?

Yes

No

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Under penalties of perjury, I declare that I have examined this application, and accompanying schedules and statements, and, to the best of my knowledge and
belief, they are true, correct, and complete.

Sign
Here

Signature

Title

Date

Type or print name below your signature.

Activity Letter

Additional Information Required

A

Manufacturer of gas guzzler
automobiles, sport fishing equipment
(including fishing rods and fishing poles),
fishing tackle boxes, bows, quivers,
broadheads, points, arrow shafts,
taxable tires, or vaccines.

1. List all articles you manufactured. Include advertising brochures, if available.
2. List the organizations or businesses (for example, state or local government or school) to which
you intend to sell articles tax free.
3. List the monthly volume of tax-free articles you intend to sell. Also, list the monthly volume of
taxed articles you intend to sell.

B

Buyer of sport fishing equipment
(including fishing rods and fishing poles),
fishing tackle boxes, gas guzzler
automobiles, bows, quivers,
broadheads, points, or vaccines for
further manufacturing or for resale to a
buyer for further manufacturing.

1. List articles you intend to purchase for further manufacturing or for resale for use by the buyer for
further manufacturing.
2. List the businesses that you will sell articles to for use in further manufacturing, if applicable.
3. List your other types of sales of articles other than for further manufacturing.

C

Buyer of taxable tires for use on or in
connection with the sale of another
article the buyer manufactures and sells
(1) for export, (2) to state and local
governments, (3) to nonprofit
educational organizations, or (4) as
supplies for vessels or aircraft.

1. List the type and weight of the tires you bought.
2. List the articles you manufactured (a) on which the tires will be used, or (b) in connection with
which the tires will be sold.
3. List the organizations or businesses with which you intend to have tax-exempt sales.

D

Buyer with a place of business in the
United States purchasing vaccines, gas
guzzler automobiles, taxable tires, sport
fishing equipment (including fishing rods
and fishing poles), fishing tackle boxes,
bows, quivers, broadheads, points, or
arrow shafts for export or for resale to a
second purchaser for export.

1. List the articles you intend to buy for export or resale to others for export.
2. List the businesses to which you intend to sell articles for export.

E

Buyer (other than state or local
government) of gas guzzler automobiles
for ambulance, law enforcement, or
firefighting.

Provide the general information for all applicants.

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Form 637 (Rev. 12-2022)

Activity Letter

Additional Information Required

F

Nonprofit educational organization, other
than a public school, buying taxable
tires, certain heavy vehicles, sport
fishing equipment (including fishing rods
and fishing poles), fishing tackle boxes,
bows, quivers, broadheads, points, or
arrow shafts for its exclusive use.

1. Provide a general description of the type of your educational facility, including faculty, curriculum,
and student body.
2. Provide a copy of the IRS determination letter granting your exemption from federal income tax.
3. List products subject to federal excise tax you bought for the exclusive use of your organization
and how the products will be used in the operation of your organization.
4. List activities (other than educational) conducted by the organization.

G

Persons making inventory exchanges of
taxable chemicals under section
4662(c)(2) or persons selling or buying
intermediate hydrocarbon streams under
section 4662(b)(10).

1. List the taxable chemicals you exchange. List the intermediate hydrocarbon streams you sell or
buy.
2. Describe your processing plants, products produced, handling and storage facilities, and
processes involving hydrocarbon streams, if applicable.

I

Buyer (other than nonprofit educational
organization or state or local
government) of taxable tires for use on
certain intercity, local, or school buses.

1. List types and weights of tires you bought.
2. Describe the types of buses (intercity, local, or school) on which the tires are used.
3. Describe how the buses are used in the operation of the business.

K

Buyer of kerosene for a feedstock
purpose.

List the type of kerosene you purchased, and describe the product and manufacturing process for
which the kerosene will be used as a feedstock.

M

Blender of gasoline, diesel fuel
(including a diesel-water fuel emulsion),
or kerosene, producing a taxable fuel
outside the bulk transfer/terminal
system, including blenders of alcohol
fuel mixtures, alternative fuel mixtures,
biodiesel mixtures, and renewable
diesel mixtures.

1. List the products you bought or produced for blending with gasoline, diesel fuel, or kerosene.
2. List the annual volume of products you bought for blending.
3. List the annual volume of blended taxable fuel you produced.

Q

First retail seller of certain heavy
vehicles.

1. Describe the heavy vehicles you intend to sell.
2. Describe the exempt sales of the heavy vehicles you intend to make.

S

Enterer, position holder, refiner, terminal
operator, or throughputter of gasoline,
diesel fuel (including a diesel-water fuel
emulsion), or kerosene, or industrial user
of gasoline.

1. List the annual volume of gasoline, diesel fuel, and kerosene you entered into the United States or
produced.
2. List the locations and a description of your refineries, terminals, and pipelines.
3. List the names and addresses of any person(s) who will be acting for you as an agent or broker in
entering, buying, selling, or transporting any fuel.
4. List the business entities to whom you sell and with which you buy, trade, transfer, or exchange
any gasoline, diesel fuel, and kerosene.
5. Provide the annual volume of gasoline, diesel fuel, and kerosene you buy, sell, trade, transfer, or
exchange.

V

Manufacturer, importer, or buyer of
ozone-depleting chemicals (ODCs) for
export.

1. List the ODCs you import or manufacture for export.
2. List the companies from which you buy ODCs for export.
3. List the number of pounds for each type of ODC you exported in this calendar year and an
estimate for next calendar year.
4. List your export locations, and list your production allowance, consumption allowance, export
allowance, and export percentage as set by the Environmental Protection Agency.

X

Pipeline operator or vessel operator
(including certain deep-draft vessels)
within the bulk transfer/terminal system.

1. Schematic or map of your pipeline locations.
2. Names and addresses of facilities served by your pipeline or vessel.
3. Number, description, and capacities of your vessels used to transport taxable fuel.

Y

Buyer of kerosene for its use in
commercial aviation (other than foreign
trade).

1. List the quantity, types, and gross take-off weights of all aircraft you own and/or operate. Include
the countries of registration. Aircraft that you operate but that are owned by other persons should be
clearly designated. Information should be included as to the operating arrangements.
2. List the average number of operating hours (per month) of each aircraft that is listed in item 1.
Show the number of hours for commercial aviation (other than foreign trade) and noncommercial
aviation.
3. If you maintain kerosene storage facilities, list the location and capacity of each facility.

AB Producers and importers of
agri-biodiesel.

1. List the annual volume of agri-biodiesel you produced in or entered into the United States.
2. List the locations and a description of your production facilities.
3. List the names and addresses of any person(s) who will be acting for you as an agent or broker in
entering, buying, selling, or transporting any agri-biodiesel.
4. List the business entities to whom you sell and with which you buy, trade, transfer, or exchange
any agri-biodiesel.
5. Provide the annual volume of agri-biodiesel you buy, sell, trade, transfer, or exchange.

AF Producers and importers of alcohol.

1. List the annual volume of alcohol you produced in or entered into the United States.
2. List the locations and a description of your production facilities.
3. List the names and addresses of any person(s) who will be acting for you as an agent or broker in
entering, buying, selling, or transporting any alcohol.
4. List the business entities to whom you sell and with which you buy, trade, transfer, or exchange
any alcohol.
5. Provide the annual volume of alcohol you buy, sell, trade, transfer, or exchange.
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Form 637 (Rev. 12-2022)

Activity Letter

Additional Information Required

AL Alternative fueler that sells for use or
uses alternative fuel as a fuel in a motor
vehicle or motorboat.

Provide the general information for all applicants.

AM Alternative fueler that produces an
alternative fuel mixture that is sold for
use or used in the alternative fueler’s
trade or business.

Provide the general information for all applicants.

BC Qualified blood collector organization
buying taxable fuel, taxable tires, and
certain heavy vehicles; claiming
exemption from the communications
tax and heavy highway vehicle use tax;
or to claim a credit or payment of
certain excise taxes, for its exclusive
use in the collection, storage, or
transportation of blood.

1. Provide a general description of your blood collection activity.
2. Provide a copy of the IRS determination letter granting you an exemption from federal income tax
under section 501(a) as an organization described in section 501(c)(3).
3. Provide evidence of your registration with the Food and Drug Administration as a blood collector.

CC Credit card issuer that issues credit
cards for sales of taxable fuel to a state
or local government for its exclusive use
or for sales of gasoline to a nonprofit
educational organization for its exclusive
use.

Provide the general information for all applicants.

NB Producers and importers of biodiesel
(other than agri-biodiesel) and renewable
diesel.

1. List the annual volume of biodiesel and renewable diesel you produced in or entered into the
United States.
2. List the locations and a description of your production facilities.
3. List the names and addresses of any person(s) who will be acting for you as an agent or broker in
entering, buying, selling, or transporting any biodiesel and renewable diesel.
4. List the business entities to whom you sell and with which you buy, trade, transfer, or exchange
any biodiesel and renewable diesel.
5. Provide the annual volume of biodiesel and renewable diesel you buy, sell, trade, transfer, or
exchange.

QR Qualified retailer of diesel fuel or
kerosene sold in Alaska for nontaxable
uses.

Provide the general information for all applicants.

SA Producers or importers of sustainable
aviation fuel.

1. List the annual volume of sustainable aviation fuel you produce.
2. List the locations and a description of your production facilities.
3. List the feedstocks and sources of feedstocks used to produce the sustainable aviation fuel.
4. Provide a statement indicating whether you produce sustainable aviation fuel under an ASTM
D7566 Annex or ASTM D1655 Annex A1, and, if applicable, the specific ASTM D7566 Annex under
which the SAF synthetic blending component is produced.
5. Provide a sample Certificate of Analysis for the type of sustainable aviation fuel you produce,
demonstrating conformance with either an ASTM D7566 Annex or ASTM D1655 Annex A1.
6. Provide certification from the International Sustainability and Carbon Certification (ISCC),
Roundtable on Sustainable Biomaterials (RSB), or other unrelated party demonstrating compliance
with (i) any general requirements, supply chain traceability requirements, and information transmission
requirements established under CORSIA, which has been adopted by the ICAO with the agreement of
the United States; or (ii) any similar methodology that satisfies the criteria under section 211(o)(1)(H) of
the Clean Air Act (42 U.S.C. 7545(o)(1)(H)), as in effect on August 16, 2022.
7. Provide certification in accordance with section 40B(e) that the SAF synthetic blending component
has a lifecycle greenhouse gas emissions reduction percentage of at least 50%.
8. List the names and addresses of any person(s) acting for you as an agent or broker in buying,
selling, or transporting any sustainable aviation fuel.
9. List the business entities to which you sell sustainable aviation fuel.
10. List the business entities from or with which you buy, trade, transfer, or exchange any sustainable
aviation fuel.
11. List the annual volume of the sustainable aviation fuel you buy, sell, trade, transfer, or exchange.

SB Producers of second generation
biofuel.

1. List the annual volume of cellulosic biofuel (including second generation biofuel) you produced in
the United States.
2. List the plant material you used to produce the cellulosic biofuel (including second generation
biofuel).
3. List the locations and a description of your production facilities.
4. List the names and addresses of any person(s) who will be acting for you as an agent or broker in
buying, selling, or transporting any cellulosic biofuel (including second generation biofuel).
5. List the business entities to whom you sell and with which you buy, trade, transfer, or exchange
any cellulosic biofuel (including second generation biofuel).
6. Provide the annual volume of cellulosic biofuel (including second generation biofuel) you buy, sell,
trade, transfer, or exchange.
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Form 637 (Rev. 12-2022)

Activity Letter

Additional Information Required

UA Ultimate vendor that sells kerosene for
use in aviation.

Provide the general information for all applicants.

UB Ultimate vendor that sells undyed diesel
fuel or undyed kerosene for use in
certain intercity and local buses.

Provide the general information for all applicants.

UP Ultimate vendor that sells kerosene
from a blocked pump.

1. Describe the blocked pumps you used to sell kerosene in your business.
2. List the location of your blocked pumps.

UV Ultimate vendor that sells (a) undyed
diesel fuel or undyed kerosene to a state
or local government for its exclusive use,
or (b) gasoline (including aviation
gasoline) to a state or local government
for its exclusive use or to a nonprofit
educational organization for its exclusive
use.

Provide the general information for all applicants.

Section references are to the Internal Revenue Code unless
otherwise noted.

Pub. 510, Excise Taxes, has more information regarding
registrations.

Future Developments

Penalty

For the latest information about developments related to Form
637 and its instructions, such as legislation enacted after they
were published, go to www.irs.gov/Form637.

The penalty for failure to register, if you’re required to register, is
$10,000 for the initial failure, and $1,000 for each day following
that you fail to register. The penalty applies unless the failure to
register is due to reasonable cause.

What’s New
Activity letter SA. The Inflation Reduction Act of 2022 enacted
the section 40B sustainable aviation fuel credit for certain fuel
mixtures containing sustainable aviation fuel sold or used after
December 31, 2022. The IRS designated SA as the activity letter
related to this credit. See Notice 2023-06.

Reminder
Reinstatement of activity letter G. The Infrastructure
Investment and Jobs Act reinstates the excise taxes imposed
on certain chemical substances by sections 4661 and 4671,
effective July 1, 2022. Activity letter G is reinstated for persons
making inventory exchanges of taxable chemicals under section
4662(c)(2), or persons selling or buying intermediate
hydrocarbon streams under section 4662(b)(10). See Notice
2021-66, 2021-52 I.R.B. 901, available at www.irs.gov/
irb/2021-52_IRB#NOT-2021-66.

How To Apply
Complete Form 637 and submit it with the required additional
information described on the chart on pages 2–5. You may use
additional sheets for your explanations. Write your name and
EIN on each sheet you attach. You must send all of the required
information or the processing of your application will be
delayed. The IRS will ask you for additional information if
needed, or you may provide additional information at any time.

General Instructions

The application must be reviewed and approved before you’re
registered for any activity, and bond may be required. The
review may include inspection of your premises during normal
business hours without advance notice. If your application is
approved, the IRS will issue a Letter of Registration. The letter
will include the activities you’re registered for, the effective date
of the registration, and your registration number. A copy of Form
637 isn’t a Letter of Registration. If your application is denied,
you will be notified by the IRS in writing, including the reason for
the denial.

Purpose of Form

Employer Identification Number (EIN)

Use Form 637 to apply for excise tax registration for activities
under sections 4101, 4222, 4662, and 4682. See the chart on
pages 2–5 for the list of activities. Each business unit that has,
or is required to have, a separate EIN is treated as a separate
person.

Enter your EIN. If you don’t have an EIN, you may apply for one
online by visiting www.irs.gov/EIN. You may also apply for an
EIN by faxing or mailing Form SS-4, Application for Employer
Identification Number, to the IRS.

The following persons must be registered.
• Pipeline operator or vessel operator: activity letter X.
• Enterers, position holders, refiners, and terminal operators:
activity letter S.
• Blenders: activity letter M.
• Producers or importers of alcohol, agri-biodiesel, and
biodiesel (including renewable diesel): activity letters AF, AB,
and NB, respectively.
• Producers or importers of sustainable aviation fuel: activity
letter SA.
• Producers of second generation biofuel: activity letter SB.
Current CB registrants will not need to reapply for new SB
registrations.

P.O. Box
If the post office doesn’t deliver mail to your street address and
you have a P.O. box, show the box number instead of the street
address.

Signature
Form 637 must be signed by a person with authority to bind the
applicant.
The authority to bind means the ability to execute agreements
that are binding and legally enforceable against the applicant
under state law. Form 637 submitted by:
• An individual or sole proprietorship—must be signed by that
individual;
• A partnership—must be signed by any one of the general
partners;
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Form 637 (Rev. 12-2022)

• A limited liability company (LLC)—must be signed by a
person that complies with the federal tax treatment of the LLC;
if the LLC is taxed as a partnership, then Form 637 must be
signed by a member manager of the LLC; if the LLC is taxed as
a corporation, then the rules for corporations must be followed;
• A corporation—must be signed by the president, vicepresident, treasurer, assistant treasurer, chief accounting
officer, or any other officer duly authorized to act for the
corporation;
• A government agency—must be signed by any person legally
authorized to act for the agency;
• A tax-exempt organization—must be signed by any person
legally authorized to act for the organization; if the organization
is a corporation, the rules for corporations must be followed; if
the entity is a trust or other type of entity, those rules must be
followed; or
• An estate or trust—must be signed by a fiduciary or
authorized representative.

Where To Apply
Fax Form 637 to 855-887-7735 or send to:
Department of the Treasury
Internal Revenue Service
Excise Operations Unit—Form 637
Mail Stop 5701G
Cincinnati, OH 45999

See the Instructions for Form 720 for a list of notices providing
additional guidance.
Privacy Act and Paperwork Reduction Act Notice. We ask for
the information on Form 637 to carry out the Internal Revenue
laws of the United States. We need it to figure and collect the
right amount of tax. Subtitle D of the Internal Revenue Code,
Miscellaneous Excise Taxes, imposes certain excise taxes.
Section 4101 requires certain persons to register for excise
taxes on fuel, as imposed by sections 4041 and 4081. Sections
4101, 4222, 4662, and 4682 allow certain other manufacturers,
sellers, or purchasers to register to be eligible for credits or to
be exempt from the excise tax on taxable articles. If you’re
required to register under section 4101 or if you elect to register
for credits and/or exemption, you’re required to provide the
information requested on this form. Failure to provide this
information may subject persons required to register to
penalties, and may delay or prevent the processing of a
voluntary registration for credits or exemption; providing false
information may subject you to penalties. Section 6109 requires
you to provide the requested identification numbers.
You’re not required to provide the information requested on a
form that is subject to the Paperwork Reduction Act unless the
form displays a valid OMB control number. Books or records
relating to a form or its instructions must be retained as long as
their contents may become material in the administration of any
Internal Revenue law.

If an IRS office has issued you a Certificate of Registry or a
Letter of Registration that is still in effect for an activity, you
don’t have to reapply for registration for that activity unless
notified to do so. However, see Reregistration for fuel activities
under section 4101, later. To confirm the status of a registration,
visit https://apps.irs.gov/app/exciseTax/. To apply for another
activity or to cancel a registration, you must contact the IRS
office in which you’re registered.

Generally, tax returns and return information are confidential,
as required by section 6103. However, section 6103 allows or
requires the IRS to disclose or give such information to the
Department of Justice for civil and criminal litigation; to cities,
states, the District of Columbia, and U.S. commonwealths and
possessions to administer their tax laws; and to other countries
under a tax treaty. We may also disclose this information to
federal and state agencies to enforce federal nontax criminal
laws, or to federal law enforcement and intelligence agencies to
combat terrorism.

Notify the IRS office within 10 days if any information
submitted with an application changes. This includes, but isn’t
limited to, address changes or changes in business activities. A
registrant may not sell, lease, or otherwise allow another person
to use its registration.

The time needed to complete and file Form 637 will vary
depending on individual circumstances. The estimated average
time is: Recordkeeping, 7 hr., 39 min.; Learning about the law
or the form, 1 hr., 37 min.; and Preparing and sending the
form to the IRS, 4 hr., 13 min.

Reregistration for fuel activities under section 4101. You
must reregister with the IRS if there’s a change of more than
50% of the ownership of a registrant. In this instance, a change
in ownership means that after a transaction (or series of
transactions), more than 50% of the ownership interests in, or
assets of, a registrant are held by persons other than persons
(or persons related thereto) who held more than 50% of such
interests or assets before the transaction (or series of
transactions). Reregistration doesn’t apply to companies whose
stock is regularly traded on an established securities market. If
you fail to reregister as required, see Penalty, earlier.

If you have comments concerning the accuracy of these time
estimates or suggestions for making Form 637 simpler, we’d be
happy to hear from you. You can send us comments from
www.irs.gov/FormComments. Or you can write to:

Changes in Registration

To reregister, send a newly completed Form 637 to the
address under Where To Apply, earlier. On line 1d, enter your
current registration number. The IRS will revoke the current
registration number and issue a new registration to the new
ownership (registrant).

Additional Registration Information
For registration relating to:
• Taxable fuel, see Regulations section 48.4101-1.
• Taxable chemicals, see sections 4662(c)(2) and 4662(b)(10).
• Exports of ozone-depleting chemicals, see Regulations
section 52.4682-5.
• All other articles, see Regulations section 48.4222(a)-1.

Internal Revenue Service
Tax Forms and Publications
1111 Constitution Ave. NW, IR-6526
Washington, DC 20224
Don’t send Form 637 to this address. Instead, see Where To
Apply, earlier.